Fruit tree fans or espaliers

I want to grow a fruit tree in a tub on a north facing wall against a wooden fence about 6 feet high. The position is opposite my side door so I would like the tree to cover as much of the fence as possible. The position does get a few hours of sun a day and I could easily protect it in the winter with fleece. Please help.

Does it have to be in this position? Most fruit trees want plenty of sunshine to fruit well, and won't be happy on your fence.